1. Technical Field
This disclosure relates to a waste liquid storage container, a waste liquid discharge device, and an image formation apparatus.
2. Description of the Related Art
Nowadays, waste liquids are collected and disposed of in various situations. For example, automobiles and machine tools generate waste oil upon changing oil. In the medical field, it is necessary to collect and dispose of body fluids such as blood and the like. There are various types of collection methods in which liquid is collected as is in a container, liquid is solidified and disposed of as in cases of edible oil, waste liquid is sent to a waste liquid collection unit built in a device and a waste liquid absorption unit is replaced, or the like. In each case, a common object regarding waste liquid disposal is how to collect waste liquid without spilling it out of a container.
The following describes the common object mentioned above referring to an image formation apparatus provided with a liquid discharge device as an example. In general, image formation apparatuses having functions of a printer, fax machine, copier, plotter, or multi-functionality of these functions use the liquid discharge device including a recording head constructed with a liquid discharge head for discharging droplets of recording fluid (liquid), for example. While transferring a medium (hereafter also referred to as “paper” without limiting materials and a recorded medium, recording medium, transfer material, recording paper, and the like are used as having the same definition), such image formation apparatuses perform image formation (recording, printing, photo printing, and character printing are used as having the same definition) by attaching recording fluid (hereafter also referred to as ink) to paper as liquid.
The expression “image formation apparatuses” refers to apparatuses for performing image formation by discharging liquid to a medium such as paper, string, fiber, fabric, leather, metal, plastic, glass, wood, ceramics, and the like. The expression “image formation” not only refers to providing images having meaning such as characters, figure, and the like to the medium, but also refers to providing images having no meaning such as patterns to the medium. Further, the word “liquid” is not limited to the recording fluid or ink as long as it is fluid when discharged. Moreover, the liquid discharge device refers to a device for discharging liquid from a liquid discharge head and is not limited to image formation.
Liquid discharge devices and image formation apparatuses using such a liquid discharge head require a mechanism for maintaining and recovering capability of the liquid discharge head for discharging recording fluid. Main functions of the mechanism for maintaining and recovering capability of the head include a cap function for covering with a cap member having high sealing characteristics so as to prevent thickening and fixation of the recording fluid resulting from natural evaporation of ink in the vicinity of nozzle openings, a discharge recovery function for recovering from discharge failure due to air bubbles and the like generated in the nozzle openings by ejecting the recording fluid and for performing suction and ejection of the recording fluid from the nozzle of the head through the cap function, and a wiping function for wiping out remaining recording fluid attached on a nozzle surface which may cause a change of flight conditions of droplets.
By performing such an operation for maintaining and recovering the capability of the head, recording fluid unused for recording (image formation) is ejected as waste recording fluid. Some maintenance and recovery mechanisms include a waste liquid storage container (also referred to as a waste liquid tank, waste liquid storage unit, and the like) for accumulating and storing the waste recording fluid and a fill-up detection sensor for detecting fill-up of the waste liquid storage container.    Patent Document 1: Japanese Laid-Open Patent Application No. 2005-119210    Patent Documents 2 and 3 disclose collection of waste liquid in an ink cartridge.    Patent Document 2: Japanese Laid-Open Patent Application No. 3-175048    Patent Document 3: Japanese Laid-Open Patent Application No. 4-211963    Patent Documents 4 and 5 disclose a waste liquid storage container storing a porous sponge body and a felt material disposed on a portion of an apparatus in which waste ink is collected in the waste liquid storage container.    Patent Document 4: Japanese Laid-Open Patent Application No. 60-011363    Patent Document 5: Japanese Laid-Open Patent Application No. 6-32923    Patent Document 6 discloses high water-absorbing polymers used as absorbent stored in an accumulation space of an accumulation unit.    Patent Document 6: Japanese Laid-Open Patent Application No. 10-244665
In recent years, it has become difficult to secure a space for the waste liquid storage container as image formation apparatuses have been downsized and a waste liquid absorber is directly disposed on a bottom of a device housing without using a container, for example. In this case, the bottom of the device housing usually has a complicated shape with concavity and convexity, so that this poses problems in that the waste liquid absorber needs to be processed to have such a complicated shape in order to be disposed in accordance with the complicated shape, design of the waste liquid absorber is greatly limited, and the like.
In particular, conventionally used waste liquid absorbers made of the porous sponge body and the felt material have a small amount of waste liquid which can be absorbed relative to a space occupied by the waste liquid absorber, so that this poor efficiency of space is problematic.
In this case, by using high water-absorbing polymers as disclosed in Patent Document 5, it is possible to substantially improve the space efficiency of waste liquid absorption. However, an image formation apparatus disclosed in Patent Document 5 only solves a problem of disposing of a large amount of waste ink in an ink-jet printer for fabric. It is impossible to apply this to small-sized image formation apparatuses used in homes and offices without change and there is a problem in that polymers are unevenly located in a certain portion of the accumulation space, so that waste liquid may not be collected at an early stage.